President Trump spoke to reporters from Air Force One Sunday night, answering questions from the national security advisor to an offer to send troops to Mexico to fight cartels.

National security adviser Mike Waltz is leaving his White House post, although soon after reports about his departure were published, President Trump announced he plans to nominate him to be ambassador to the United Nations.

President Donald Trump has gone through his share of national security advisers. But he doesn't hold the record, yet.